ABSTRACT
According to commonly used terminology, if E is a topological space which is not of first category on itself, then E is said to be of second category. This chapter discusses bad functions defined on second category sets. It recalls the precise formulation of the Kuratowski–Ulam theorem, which can be regarded as a reasonable topological version of the Fubini theorem. The chapter shows that any subset of the Kunen space W possesses the Baire property. Hence, any real-valued function defined on W has the Baire property. The chapter also includes exercise problems related to the concept of bad functions defined on second category sets.
